MSc thesis project proposal

clock-offset and gain mismatch invariant signal processing in radar/sonar applications

As discussed during the lectures of Digital Audio and Speech Processing (DASP, IN4182), a certain class of beamformers, the so-called speech-distortion weighted multichannel Wiener filters (SDW-MWF), if properly implemented (e.g. using the GEVD), are invariant to clock offsets and gain mismatches, which implies that these beamformers do not need to be clock synchronised and that a gain calibration is obsolete. In addition, knowledge of the steering vector is not necessary which makes these beamformers good candidates for (wireless) sensor networks, in particular ad-hoc networks where the topology is not known a priori and can possibly change during operation. Clock skew, on the other hand, is not an issue when uniform hardware is used.

In certain application, like surveillance application, sensors both transmit and receive information. Examples are radar and sonar, where the sensors first transmit a known signal, after which a possible reflection is received and detected. Alternatively, some sensors can transmit and some of them receive (like bi-static radars). The goal of this graduation project is to investigate whether the above mentioned properties still hold in such applications. In addition, in radar applications, a frequency shift (Doppler effect) is used to determine the velocity of the detected object. Hence, clock skew could be more important here than in acoustic applications. What the minimal allowed clock skew is needs to be investigated.

If the project is successful, field experiments can be done at the Royal Netherlands Navy (both sonar and radar).


Who can apply: Students who succesfully passed the IN4182 exam and have a thorough understanding of the (G)EVD approach as discussed during the lectures and have a NATO nationality. The latter is needed for doing field experiments at the Royal Netherlands Navy. Other nationalities can still apply but cannot do the field experiments.

For more information, please contact Richard Heusdens ( or Richard Hendriks (

Contact Richard Hendriks

Circuits and Systems Group

Department of Microelectronics

Last modified: 2020-07-03